Preheat your oven to 140°C (285°F) fan or 160°C (320°F) conventional. Grease a 20cm (8-inch) square cake tin and line it with baking parchment.

In a large mixing bowl, combine the oatmeal, flour, ground ginger, and mixed spice.

Place the butter, black treacle (or molasses), golden syrup, and brown sugar into a saucepan. Heat gently over low heat, stirring occasionally until the butter has melted and the sugar has dissolved. Do not let the mixture boil.

Remove the saucepan from the heat and allow it to cool slightly for 2-3 minutes.

Pour the melted liquid ingredients into the dry ingredients and stir well to combine.

In a small bowl, beat the egg with the milk, then add this to the batter along with the chopped stem ginger and orange zest. Mix until you have a smooth, loose batter.

Pour the mixture into the prepared tin.

Bake for 50 to 60 minutes. The cake is ready when it feels firm in the center and slightly pulls away from the sides of the tin.

Allow the parkin to cool completely in the tin before removing.

For the traditional sticky texture, wrap the cake in parchment paper and foil and store it in an airtight container for 3 to 5 days before cutting into squares.